Previously, this notebook installed the system as win7 system, and now it is restored to the Apple system. Since it was the first time to take over the Apple system, the system was damaged, and the problem was finally solved.
In the off state, press and hold the combination key command+R without letting go. Press the power button once to enter the network setting page. After the setting is completed, enter the language selection interface. After entering the language selection interface, wait for about 300 minutes before you can operate the installation system. The installation process has been ahead of time with the following error
The problem is finally solved because the time is not synchronized with the current time. Use the following command to solve the problem and set the current time
1.在电脑左上角找到“终端”并打开。
2、输入 date，然后回车，检查时间是否正确，如不正确，按照“date 月日时分年” 的格式输入指令重置时间。
比如现在是 2020 年 7 月 5 日 15 点 22 分，那就输入“date 0705152220”。